Lucius Malfoy Both Takes and Gives a Test
You would think that a group of fully-grown, professedly-evil wizards would have enough Dark Magic experience to satisfy your average Dark Lord. But, no. Not Voldemort. Voldemort wanted "standardization."
"I've been waiting for this all my life," he said, "and I'm not going to let you idiots mess it up with your inconsistency."
After weeks of laborious meetings and compilations, a Standards of Practice Guide for Death Eaters was published. Regular dueling recertification was instated, as well as a lengthy exam to test one's Dark knowledge.
And so, it came to pass that Snape had to administer an oral exam to one Lucius Malfoy. "You're in a dark room, lit by a single torch. There are exits to the north, south and east," read Snape off his exam.
"Um, I go north," started Lucius.
"You are in a moldy cavern. There is an exit to the east, blocked by a Muggle."
"I want to make the Muggle spontaneously combust."
"You can't make it spontaneously combust."
"What? Why can't I set it on fire?"
"You can set it on fire, but you can't make it spontaneously combust."
"That makes no sense, Snape. Is that written on the exam? I knew we shouldn't have let Crabbe on the committee."
"No," said Snape impatiently, "it's just that you can't make anything spontaneously combust. That negates the spontaneity of it."
"That's ridiculous," said Lucius. "I'm making him burst into flames out of nowhere. That's pretty darn spontaneous."
"As in 'sudden,' yes. But it's an action perpetrated by you. It's guided; it doesn't actually come out of nowhere."
At this point, their bickering had attracted the attention of Voldemort, which is never pleasant. Stomping over, Voldemort snapped, "Knock it off, both of you. No one else is going to be able to concentrate if you keep this up." Snape noticed for the first time that several other pairs of test-takers were watching them. Bellatrix's glare was especially venomous.
"But Snape won't let me set a Muggle on fire!" cried Lucius.
"I don't care! Now, apologize, both of you. And shut up!"
"I'm sorry," muttered Lucius, rolling his eyes.
"I'm sorry you don't understand how spontaneous combustion works," replied Snape.